instigator31

kfvintx...you are going to die (well not really), but you now have the 5th or 6th Formula that has the SAME exact problem. I can't say it is a Formula issue, and I can say that since I own a Formula as well, I have the SAME issue. Below is my issue: The similarity is all MERC engines and Bravo III Drives. Is that what you have?

2008 Twin 496Mag with Bravo IIII Drives.

I maintain pretty detailed records of fuel burn, GPH, MPH, RPM, etc. I have the factory installed "mechanical RPM" gauges and then two smartcraft monitors directly connected to the engine. I went on a 80 mile trip this weekend. On the way out everything was perfect...that means when I throttle up my engines, I would bring the lever's up together...and always my engines run about the same RPM on cruise, burn about the same GPH and stay in "sync".

On the trip home, we departed the marina...all was well...ran about 5 miles, then anchored out for an afternoon swim. As we left, I started out and all of a sudden my STBD engine is about 200-300 RPM's behind my Port at the same "throttle input". Makes no sense, so I think I have seaweed or something on my props...so I stop, everthing is perfect...much be my imagination.

Start up again, same thing...STBD engine needs about "1 1/2 inches" more throttle input to maintain the same rpm's as the Port engine...both gauges read this way. So I think maybe something slipped in throttle linkage...NOPE, at least not that I can tell...at the engine both throttles seem to advance exactly the same distance.

Now it gets worse...so I then end up cruising this way...meaning I have way more throttle into the STBD engine to keep the RPM's the same...and guess what, I am not burning a TON more fuel in my STBD engine...however they are now the same exact RPM. (A ton more fuel means 2 GPH, but for my boat that is way off.)

So now I think somehow my gauges are messed up? How could the fuel burn be so different. And of course, when I got back....my STBD engine did burn more fuel on the way home, vs on the way there when they both burned the same.

Any ideas...where to look first. I find it hard to believe my factory tach and smartcraft tach went at the same time. Or do they feed of the some comon point, such as the ECM, even though they are connected in different ways.

OH, I also checked the trim, they both seeem to be trimmed the same and both props show no damage.

Thanks in advance for some more ideas..

instigator31

I was also wondering if we should post this in the Techical sections instead...maybe it is not a Formula issue and others can help out? Not sure how cross posting works in this forum though? Any thoughts?

instigator31

I also compiled a list of other people having similar issues (not just forumula). Any of these items could result is issues...and other people had success at some point or another by resolving these issues.

Ground cable to battery loose
Spark Plug(s) Bad
Spark Wire Disconnected
Fuel Filter
Too much oil
engine in Guardian mode
Crankshaft position code activated
camshaft position code activated
Clear all engine codes